Enhancement Of Transfection Efficiency Using Recombinant Transferrin With Serum-Free HEK293 Media

By Sofia Pezoa, PhD, Cell Culture Scientist, InVitria

Methods to enhance transient transfection of adherent cells have identified many different ligands that improve plasmid uptake into cells. Of these ligands, serum-derived transferrin is well-known to improve transfection efficiency of adherent cells.

Given the success of transferrin as a molecular carrier, the use of transferrin has still relied on serum-derived transferrin from either bovine serum or human serum. Both of which are subject to numerous disadvantageous factors such as adventitious agents present in serum, constraints on the supply-chain, or increasing cost due to demand.

However, to date, a serum-free and blood-free transferrin has not been tested for improvements to transfection efficiency. We have thus created a protocol for the improvement of transfection efficiency and viral titer without the need for blood-derived transferrin. Excess transferrin does not negatively impact transfection, and the incorporation of a blood- and serum-free, recombinant human transferrin supports high transfection efficiency and viral titer in a chemically defined, blood-free medium.